Transcript Basic Electrical Theory - Linn

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9- 911
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Insure those in the shop are immediately
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Do not hesitate to evacuate the building
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(from a safe location)
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Read the instructions and service procedures
Ask questions
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checked out by an instructor
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unfamiliar machine or system
Locate and read manufacturer
procedures
Pay special attention to any
precautions
Ask Questions before proceeding
Basic Electrical Theory
For Electrical Current to Flow:
There must be a difference in electrical potential
or pressure called...VOLTAGE
A conductor for the amps to move through
and Resistance to control the flow of electrons
Ohms Law E=IxR
Voltage (Electromotive-force) is used up…
to push Amperage (the Intensity of the current)…
through a Resistance
Increasing resistance will lower amp flow
How will Increasing voltage affect the amp flow?
Increase
Ohms Law E=IxR
1 volt can push 1 amp through 1  of resistance
12 volts can push 12 amps through 1  of resistance
12 volts can push 1 amp through 12  of resistance
Ohms Law E=IxR
? Volts = 2 amps x 10 
20 V
14 Volts = 2 amps x ? 
7
50 Volts = ? amps x 5 
10 amps
E=IxR
30 amps 10  ? volt
E=IxR
30 amps 10  ? volt
E=IxR
30 amps 10  ? volt
E=IxR
30 amps 10  ? volt
E=IxR
? amps 7  14 volt
E=IxR
? amps 7  14 volt
E=IxR
? amps 7  14 volt
E=IxR
? amps 7  14 volt
E=IxR
12 amps ?  6 volt
E=IxR
12 amps ?  6 volt
E=IxR
12 amps ?  6 volt
E=IxR
12 amps ?  6 volt
Ohms Law E=IxR
Do first part of worksheet on simple ohms law
Ohms Law E=IxR
As Voltage increases the current will…
…increase
As Resistance increases the current will…
…decrease
As Resistance decreases the current will…
…increase
Series Circuits
A series circuit is a voltage dividing circuit
Amp flow is determined by the TOTAL resistance
All amps flow through every resistor (when in series)
As amps flow through a resistor Voltage (pressure) is
used up……(voltage drop)
The sum of the individual voltage drops equal the
source voltage
What is the total resistance?
6 ohms
How many amps flow through R1?
2 amps
What is the Volt drop across R1?
4 volt
How many volts at the connection between R1 & R2
8 volt
Simple Ohm’s Law worksheet
Part 2
Parallel Circuit
A parallel circuit is an amperage dividing
circuit
Equal voltage will drop across each resistor in a
parallel circuit
Amperage flow will vary for each resistor
The sum of the amp flow through each resistor will
equal the total amp flow out of the battery
Do the last page of the Simple
Ohms Law worksheet
When calculating total resistance you can
use this formula
Calculate Voltage and Amperage
values for a series/parallel circuit
Can’t handle the math?
Lab 5
Parallel
Circuits